1. Field of the Invention
The present invention relates to an analysis apparatus using electrophoresis and an analysis method.
2. Background Art
Conventionally, electrophoresis is used in the fields of analytical biology and analytical biochemistry. Capillary electrophoresis is known as a representative example of electrophoresis (see, for example, JP 2001-99813A and JP 2003-166976A). In capillary electrophoresis, a capillary (microtubule) filled with a buffer solution is used, and a sample is injected into the capillary. Furthermore, both ends of the capillary are immersed in the buffer solution, and in this condition, a voltage is applied inside the capillary.
Upon application of a voltage, the sample is separated while moving within the capillary. Then, the inside of the capillary is irradiated with, for example, ultraviolet rays, visible light, or infrared rays through a window provided partway along the capillary. Light transmitted through the capillary is received by a light receiving element, and thereafter analysis of the sample is conducted based on the received light, using absorptiometry.
Moreover, in recent years, electrophoresis using microchips in place of capillaries has also been proposed. Microchips are generally made up of a glass substrate provided with fine grooves, and a cover bonded to the glass substrate so as to cover the grooves. With microchips, the formation of grooves in the glass substrate is implemented by applying semiconductor manufacturing technology, and therefore, the width, depth, and number of grooves can be easily set. For this reason, microchips could play a leading role in electrophoresis in future.
Furthermore, in electrophoresis, because the migration speeds of molecules are affected by temperature, the temperature of the buffer solution needs to be managed so as to be kept within the optimal range during voltage application. For this reason, most apparatuses for performing electrophoresis (electrophoresis apparatuses) are provided with a cooling apparatus in order to suppress a temperature rise due to voltage application. Examples of the cooling apparatus that are used include an air blowing device and a Peltier element.
Incidentally, in the case of capillary electrophoresis, since capillaries have low heat capacity, the inside of the capillaries can be easily kept within the optimal temperature range simply by operating a cooling apparatus. However, with microchips, because of their higher heat capacity as compared with capillaries, it is difficult to keep the inside of the microchips within the optimal temperature range simply by arranging and operating a cooling apparatus.